Biomarker responses in flounder (Platichthys flesus) and mussel (Mytilus edulis) in the Klaipeda-Būtinge area (Baltic Sea)

During the EU project BEEP a battery of biomarkers was applied in flounder (Platichthys flesus) and the blue mussel (Mytilus edulis) collected at three locations off the Lithuanian coast (Baltic Sea) in June and September 2001 and 2002. The elevated biomarker responses in specimens sampled in September 2001 were apparently related to the extensive dredging activities in the Klaipeda port area and subsequent dumping of contaminated sediments. High concentrations of organic pollutants (organochlorines and PBDEs) were also measured in the tissues of both indicator species. In addition, response levels of genotoxicity, cytotoxicity, immunotoxicity as well as concentrations of PAH metabolites in the bile of flounder showed elevations in 2002 after an oil spill in the Būtinge oil terminal in November 2001. In flounder, biomarker measurements 10 months after the spill indicated recovery processes but in mussels a high level of genotoxicity could still be observed 22 months later. The present study illustrates the usefulness of the multi-biomarker approach in the detection of biological effects of pollution in this region of the Baltic Sea.     

The BEEP project in the Baltic Sea: overview of results and outline for a regional biological effects monitoring strategy

Field studies in the framework of the EU funded BEEP project (Biological Effects of Environmental Pollution in Marine Coastal Ecosystems, 2001-2004) aimed at validating and intercalibrating a battery of biomarkers of contaminant exposure and effects in selected indicator species in the Mediterranean, the North Atlantic and the Baltic Seas. Major strategic goals of the BEEP project were the development of a sensitive and cost-efficient biological effects monitoring approach, delivery of information and advice to end-user groups, and the implementation of a network of biomarker researchers around Europe. Based on the main results obtained in the Baltic Sea component of the BEEP the present paper summarises and assesses the applicability of biomarkers for different regions and species in this sea area. Moreover, a general strategy and some practical considerations for the monitoring of biological effects in the Baltic Sea are outlined.     

上海市区承压含水层结构类型分区

上海地区与工程建设密切相关的承压水主要赋存于微承压、第一、第二承压含水层中。本文在上海市区关键土层地质编图的基础上,针对与工程建设密切相关的承压含水层的分布特征,进行承压含水层的结构类型分区,为工程降水设计提供参考。     

Changes in zooxanthellae density,morphology, and mitotic index in hermatypic corals and anemones exposed to cyanide

Sodium cyanide (NaCN) is widely used for the capture of reef fish throughout Southeast Asia and causes extensive fish mortality, but the effect of NaCN on reef corals remains debated. To document the impact of cyanide exposure on corals, the species Acropora millepora, Goniopora sp., Favites abdita, Trachyphyllia geoffrio, Plerogyra sp., Heliofungia actinformis, Euphyllia divisa, and Scarophyton sp., and the sea anemone Aiptasia pallida were exposed to varying concentrations of cyanide for varying time periods. Corals were exposed to 50, 100, 300, and 600 mg/l of cyanide ion (CN(-)) for 1-2 min (in seawater, the CN(-) forms hydrocyanic acid). These concentrations are much lower than those reportedly used by fish collectors. Exposed corals and anemones immediately retracted their tentacles and mesenterial filaments, and discharged copious amounts of mucus containing zooxanthellae. Gel electrophoreses techniques found changes in protein expression in both zooxanthellae and host tissue. Corals and anemones exposed to cyanide showed an immediate increase in mitotic cell division of their zooxenthellae, and a decrease in zooxanthellae density. In contrast, zooxanthellae cell division and density remained constant in controls. Histopathological changes included gastrodermal disruption, mesogleal degradation, and increased mucus in coral tissues. Zooxanthellae showed pigment loss, swelling, and deformation. Mortality occurred at all exposure levels. Exposed specimens experienced an increase in the ratio of gram-negative to gram-positive bacteria on the coral surface. The results demonstrate that exposure cyanide causes mortality to corals and anemones, even when applied at lower levels than that used by fish collectors. Even brief exposure to cyanide caused slow-acting and long-term damage to corals and their zooxanthellae.     

大绝灭后的生物复苏

对生物复苏的一些关键问题提供了一些线索。概述了人们如何看待生物复苏、复苏的总体型式、哪些类群会复苏及如何幸存下来，绝灭和复苏之间的联系。随着研究的深入，许多问题得到了解决，也将提出一些新的假设。     

在地球科学与社会中岩石学的地位何在？

美国国家科学院出版社于１９９３年出版了美国对地球科学的首次国家级学科调查报告－《固体地球科学与社会》。报告的中心思想是建议大力支持对整个地球体系进行研究。本文总结了报告中列出的许多研究机会，其中包括火成岩和变质岩岩石学，证实在目前提倡研究的绝大部分重要地球作用中岩石学均有强烈的体现。岩石学以其观察、测量、实验与理论密切相结合而在各领域的前沿不断发展，并将继续成为多学科地球科学研究中一个重要的基础课     

Impacts of human activities on coral reef ecosystems of southern Taiwan: a long-term study

In July 2001, the National Museum of Marine Biology and Aquarium, co-sponsored by the Kenting National Park Headquarters and Taiwan's National Science Council, launched a Long-Term Ecological Research (LTER) program to monitor anthropogenic impacts on the ecosystems of southern Taiwan, specifically the coral reefs of Kenting National Park (KNP), which are facing an increasing amount of anthropogenic pressure. We found that the seawater of the reef flats along Nanwan Bay, Taiwan's southernmost embayment, was polluted by sewage discharge at certain monitoring stations. Furthermore, the consequently higher nutrient and suspended sediment levels had led to algal blooms and sediment smothering of shallow water corals at some sampling sites. Finally, our results show that, in addition to this influx of anthropogenically-derived sewage, increasing tourist numbers are correlated with decreasing shallow water coral cover, highlighting the urgency of a more proactive management plan for KNP's coral reefs.     

MTBE and gasoline hydrocarbons in ground water of the United States

The occurrence of methyl tert-butyl ether (MTBE) and gasoline hydrocarbons was examined in three types of studies of ground water conducted by the U.S. Geological Survey: major aquifer surveys, urban land-use studies, and agricultural land-use studies. The detection frequency of MTBE was dependent on the study type, with the highest detection frequency in urban land-use studies. Only 13 ground water samples from all study types, or 0.3%, had concentrations of MTBE that exceeded the lower limit of the U.S. EPA's Drinking-Water Advisory. The detection frequency of MTBE was highest in monitoring wells located in urban areas and in public supply wells. The detection frequency of any gasoline hydrocarbon also was dependent on study type and generally was less than the detection frequency of MTBE. The probability of detecting MTBE in ground water was strongly associated with population density, use of MTBE in gasoline, and recharge. Ground water in areas with high population density, in areas where MTBE is used as a gasoline oxygenate, and in areas with high recharge rates had a greater probability of MTBE occurrence. Also, ground water from public supply wells and shallow ground water underlying urban land-use areas had a greater probability of MTBE occurrence compared to ground water from domestic wells and ground water underlying rural land-use areas. The probability of detecting MTBE in ground water was weakly associated with the density of leaking underground storage tanks, soil permeability, and aquifer consolidation, and only concentrations of MTBE >0.5 microg/L were associated with dissolved oxygen.     

Atmospheric nitrogen deposition from a remote source enriches macroalgae in coral reef ecosystems near Green Turtle Cay, Abacos, Bahamas

Over the past several decades, the fixation of "new" nitrogen to the biosphere has doubled. For the early 21st century, the most significant rate increases in atmospheric nitrogen deposition are predicted for developing nations. Wet nitrogen deposition was assessed on the remote island of Green Turtle Cay, Bahamas in a dry and wet season from January to July 2000. Episodic deposition of nitrate (approximately 1-137 microM) and ammonia (approximately 2-122 microM) represented a mean deposition rate of approximately 0.2 mgDIN m(-2) yr(-1). Wet deposition of nitrogen to the climatologically-linked east coast of Florida is approximately 4 times greater than the estimated annual wet nitrogen deposition value at Green Turtle Cay, suggesting the continental US as a principal airshed for this loading source. Short-term bioassays of macroalgal productivity with a 5% rainfall solution caused depressed net productivity and increased dark respiration, well known "transient metabolic" responses by nutrient-limited tropical macroalgae. Wet deposition of inorganic nitrogen from episodic rainfall events may provide up to 20% of the "new" nitrogen necessary to meet growth demands of macroalgae on coral reefs near Green Turtle Cay.